RCB

Ok, as a recap someone had crawled under my wife's 97zj and cut out the cat and yanked the 02 along with it. She was driving it home and it died on the way. Have not been able to get it restarted yet.

I have replaced the O2 sensor. It has spark and I can smell strong gas fumes coming from the exhaust. I haven't checked fuel pressure yet, but I would think it should have enough, but I will check it tonight to be sure. It isn't hitting at all. I would think there should be enough residual fuel after a few moments of cranking that it should at least backfire or at least make some audible sign of ignition.

I have looked through all the fuses I can, including the batch under the hood (the ASD seems to be ok).

Should I check the map sensor or anything else that may have gotten fried when the o2 wires were dangling? Though I would have thought the fuses should have gone first if anything.

Anyone have thoughts or recommendations?

SeriousOffroad

Test your Crank Position Sensor, probably gave up the ghost.

Gee oh Dee

Crakn position sensor is a common problem in the 4.0 motors.

Hommersimpson

Unplug battery for a few minuts reset computer... pull spark plugs and look at them.. if they are soaked.. it will never start... if you smell gass.. then there is enough pressure...Im going to bet your plugs are toast.. replace them..

2Evil4U

If there's that much gas, I'd unplug the fuel pump relay and crank it until it clears out. Then I'd squirt a little ether into the TB to see if it will run on that. if it will, then something in the fuel control loop is your problem.

RCB

Ok, this is really a head scratcher.

So I tested the computer at the CPS harness. I got 5v constant from the computer. So while slowly spinning the crank, I backprobed the red/white "signal" and it would spike to 5v.

For a little bit I didn't think it was working at all, but then slowing down the turning it finally picked up the 5v

So, it has gas (still smells like it's flooding), spark and it seems that the CPS is working.

Any other thoughts?

freegdr

http://www.jeep4x4center.com/knowled...ex.htm#service go here and there should be helpfull info

MallCrawlXJ

check all of your main fuses under the hood.

my o2 sensor wires on my work van hit the exhaust and melted, shorting them together. it blew a main fuse under the hood and it died. it would crank and crank, but wouldnt start.

im talkin the big daddy fuses.


hope that helps.

hud

RCB

You know, I had swapped them around to check and it didn't help, but maybe more than one is blown? Anyone know which terminals should have continuity on those?